IL1B and atherosclerosis: IL-1β, a key pro-inflammatory cytokine implicated in atherosclerosis progression and plaque formation[19], was widely expressed in the aortic arch of both MerTKflox/flox mice and MerTKflox/floxTie2Cre mice but was predominantly localized to the endothelium of MerTKflox/floxTie2Cre mice (Fig. 3A).